Knife sharpener



FIG. 1 is a front isometric view of a knife sharpener, embodying the new design.

FIG. 2 is a front view of the design of FIG. 1.

FIG. 3 is a rear view of the design of FIG. 1.

FIG. 4 is a top plan view of the design of FIG. 1.

FIG. 5 is a bottom plan view of the design of FIG. 1.

FIG. 6 is a right side view of the design of FIG. 1.

FIG. 7 is a left side view of the design of FIG. 1.

FIG. 8 is a second isometric view of the knife sharpener, wherein the sharpening rod is shown in the extended position.

FIG. 9 is a front view of the design of FIG. 8; and,

FIG. 10 is a bottom plan view of the design of FIG. 8. 

CLAIM The ornamental design for a knife sharpener, as shown and described. 